Switching and starter apparatus of electric motors



14 192 June 7 H. O.-BREE SWITCHING AND STARTER APPARATUS 0F ELECTRIC MOTORS Filed Aug. 28, 1926.

Patented June 14, 1927.

UNITED srArEs r rrica.

HELIER OSWALD BREE, 0F AUCKLAND, NEW ZEALAND.

SWITCHING- .AND STARTER APPARATUS OF ELECTRIC MOTORS-o Application filed August 28, 1926, S

This invention relates to the switching and starter apparatus for electric motors and has been devised to eliminate the danger and damage to appara possibility of putti the main switch w tus and machinery by the ng into operative position hen the starter itself is already in the on or in any intermediate position.

When the main switch is put in and the starter is inadvertently not in the normal ofi position there is a resultant heavy rush of current to the switch, starter, wiring of the motor, and other adjacent parts and there :is a grave possibility of such rush causing fusing of the parts or burning out of the armature and in some instances even injury to the person putting in theswitch. The

possibility of this error happening is by no means. slight and is especially likely when the starter must sitjon manually.

The invention which may b be returned to the oil' p0- e adapted to the main switch controller and starter of any usual type o"f.electric motor is so devised that the main switch is prevented from being put into operative position power supply is ofi and/or when at any other The idea un may switch and starter appar when the starter is than thevcorrect oil position. derlying this invention which adapted to any usual type of main atus for electric motors is to provide means whereby the above disadvantages and dangers are eliminated and to provi switch remain de means whereby the main 5 locked in an lnoperative position while either the mainpower supply is cut ofi from any starter is not in its invention the operator can at once tell byof throwing into' the impossibility b h ther or ot position the main switch that ei ofl position.

cause and/or while the By this operative ina which illustrate one cons ment incorporating the invention, Figure 1 is a of a common main switch view safety means in position, Fi

SPBCtlVB view of a common with the safety 'means in position,

drawings tructional embodithe principle underlying sectional end with the gure 2 is a perform of starter and Figerial No. 132,226, and in New Zealand July 31, 1926.

ure 3 is a view partially in perspective showing the working parts in position and the wiring arrangement.

lt-eterring now to the drawings a common type of main switch four contacts 2, 35 4,

1 is illustrated having and 5 and a leader 6 with two U contact plates 7 and 8. a handle 9 swivellcd on pin 10 to the lever Grbeing provided. The plates '4' and 8 engage in thepairs of contacts 2, 3, and 4, 5 respectively in the usual way. The said switch 1 is provided with a lug 11 on its cover 12 to which is pivotally mounted a movable catch lever 13 carrying an armature 14, on its outer face,

and a stop piece 15 at its inner upper end and a projection or flange 16 at its inner lower end having an inclined outer face 1?.

Means such as a spring 18 or the like attached to raid lever 13 and to cover 12 tend to draw the latter towards (said cover.

projection 19 with an inclined upper -taco 20 is provided on lever 6.

Also attached to said cover 12 is an electric magnet 21 so arranged and disposed as to be in close proximity when energized.

to said armature 14 which it attracts The handle 9 of the switch 1 is provided with contact make and break means such as a push button 22 normally kept from making contact with its contact piece 24: in said handle by means such as a spring 23.

Referring now to the starter portion of the apparatus a common type of starter 25 has an insulated contact box 28 fitted on its outer face said box 28 being provided with aspiring contact 29 and also a plunger con tact 30 with a knob a spring 32 tween the latter and the contacts 29 and 30 apart. The starter lever 27 has a quadrant or keep 31 projecting therefrom or the like means pressing bethe box 28 tending to the like 26 which is so disposed in relation to said knob 31 as to the starter is in the ofi bear against it when position and thus againstthe action of the spring 32 keep the contacts 29 and 30 together. The main sup ply power wires 33 and 34 pass to the contacts 2 and 1 respectively and wires 24 and pass from the terminals starter 25 and fromthence to the motor.

3 and 5 to the A wire 37 passes from the terminal 2 to the contact piece 24 while a wire 38 passes from the push button 22 ing of the passes from to one end 39 of the windelectromagnet 21. the other end 41 of said electro- A wire ,40 v

' energizing magnet 21 winding to the spring contact 29 while a further Wire 42 passes from the plunger contact 30 to the terminal 4.

Assuming for the moment that power is on in the main wires 33 and 34: and the main switch 1 and the starter 25 to be both in the oil position as shown in Figures 1 and 2 the spring 18 naturally draws the lever 13 so that its projection 16 is over the projection 19 of the switch lever 6-thereby making it impossible for the switch 1 to be put on by moving the handle 9 in the direction of the arrow shown in Figure 1. To start the apparatus it being assumed that both the power is on and the starter is in the oil position the push button 22 is pressed downwardly thereby energizing the electromagnet 21 which attracts the armature 14 thus drawing the ends 16 of the lever 13 out of juxtaposition with the pro jection 19 of said lever 6 thus enablin the switch 1 to be pushed in the direction sliowr. by the arrow in Figure 1 into the. on' position.

It will be obvious that theenergizing of said electromagnet 21 is caused by the push button 22 making contact with the contact piece 24 current thereby passing from wire 37 to wire 38 and from thence to the electromagnet 21 end 39. Current also asses from wire 32 through plunger to spring contact 29 these two always touchin each other when the starter 25 is in the off position, the current then passing from the contact 29 to the electromagnet 21 and 4:1 by way of wire 40 completes the electrocircuit and said magnet 21. The main switch 1 being on the handle 9 is released and the spring 23 forces the push button 22 away from the contact 24 and the circuit to the electromagnet 2 1 is thus broken.

It will be noticed that when the starter handle 27 is moved on the quadrant 26 passes clear of the knob 31 and the spring 32 forces plunger contact 30 away from the spring contact 29 and when the main switch 1 is on the lever 13 is drawn by a spring 18 until stop 15 is against the cover 12.

On the main switch 1 being switched off the inclined piece 20 of the lever 6 and the inclined piece 17 of the catch lever 13 come together and the latter is forced outwardly against the tension of its spring 18 until the projection 16 slides over the projection 19 thereby-locking the main switch until the electromagnet 21 is again ener ized. It will be noted that at all times un ess the quadrant 26 of starter 27 is-pressing knob 31 for opening and closing an electric circuit,

a handle for said circuit breaker, a starting resistance, a controller arm for varying said resistance, a latch for holding said circuit breaker in open position, an electromagnet adapted when energized to release said latch, a pair of circuit closing switches in series with said electroinagnet and normally open when said resistance is cut out, means on said handle for closing one of said switches, and means on said controller arm for closing the other of said switches when the resistance is in series with the circuit.

2. In combination with a circuit breaker for opening and closing an electric circuit, a handle for said circuit breaker, a starting resistance, a latch for holding said circuit breaker in open position, an electromagnet adapted when energized to release said latch and a pair of circuit closing switches in series with said electromagnet, one of said switches being disposed within said handle, the other of said switches being open when a portion of said resistance is cut out.

3. In combination with a circuit breaker for opening and closing an electric circuit. a handle for said circuit breaker, a starting resistance, a latch for holding said circuit breaker in open position, an electromagnet adapted when energized to release said latch, a pair of circuit closing switches in series; with said electromagnet, one of said switches being disposed within said handle and being normally open, means on said handle for closing the switch inthe handle, and means for holding open the other of said switches when a substantial portion of said resistance is cut out.

- In testimony whereof I aflix my signature.

HELIER OSWALD BREE. 

